1 Peter 2:2-3, "As newborn babes, desire the sincere milk of the word, that ye may grow thereby: If so be ye have tasted that the Lord is gracious."
Peter is not necessarily describing the Christians he is writing to here as babies. He's not rebuking them for being young Christians.
Instead, he is using a word picture of a baby drinking milk to show us how a Christian is to yearn for spiritual nourishment from the Lord. Continuing with this word picture he says "if you have tasted the Lord is gracious". The "if" here does not imply they would say the Lord is not gracious, but instead means "since you know how good the Lord is, how good it tastes to receive spiritual nourishment from the Lord".
Does Peter have the Psalms in the back of his mind when he is writing his letter? Psalm 34:8, "O taste and see that the Lord is good: blessed is the man that trusteth in him."
The idea of Jesus as spiritual food is all through the New Testament and is taught by the Lord Jesus himself. He told his followers he is the bread of life and he is living waters. He taught people he would give them water so they would never thirst again. He told his disciples at the last supper they would eat his flesh and drink his blood.
All of this is teaching in word pictures, not teaching in literal terms. Some attempt to interpret this literally so that when we take communion we eat the body of Christ all over again and make it into a ritual to earn salvation.
Jesus said the words he spoke were spirit and life. When we commune with Christ in prayer and through the study of his word we enjoy spiritual food and drink. It is more than mouthing a prayer, more than forcing ourselves to read a chapter in the bible every day. There is real communion with the Lord and touching the Lord through these activities in which our spirit is fed and refreshed.
Let us taste and see the Lord is good. Let us draw near to God like a baby draws near to her mother for milk. This is how close the Lord is to us. We can draw near to God, and He draws near to us. He feeds our spirit with bread of life and satisfies our thirsty soul with living waters. Amen.